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Ghasemi, J.;Shiri, F.
- Journal of the Korean Chemical Society
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- v.51 no.1
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- pp.21-30
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- 2007
A multiwavelength spectrophotometric titration method was applied to study protolytic constants of four water-soluble vitamins, folic acid(vitamin B9 or B0), thiamine(vitamin B1), riboflavin(vitamin B2) and pyridoxal (vitamin B6) in binary ethanol-water mixtures at 25oC and an ionic strength of 0.1M NaNO3. The protolytic equilibrium constants, spectral profiles, concentration diagrams and also the number of components has been calculated from the curve fitting of the pH-absorbance data with appropriate mass balance equations by an established factor analysis model. DATAN program was used for determination of acidity constant and SPECFIT program was used for calculation of standard deviations and partial correlation coefficients. A glass electrode calibration procedure based on the four parameter equation pH=α+SpcH+JH+[H+]+ JOH-Kw/[H+] based on the Gran,s plots was used to obtain pH-readings in the concentration scale (pcH). The effect of the solvent on the protolytic constants was discussed.
https://doi.org/10.5012/jkcs.2007.51.1.021 인용 PDF KSCI KPUBS HTML

Choi, E.Y.;Cho, J.R.;Cho, Y.U.;Jeong, W.B.;Lee, S.B.;Hong, S.P.;Chun, H.H.
- Structural Engineering and Mechanics
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- v.54 no.5
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- pp.909-922
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- 2015
The dynamic response and the mooring line tension of a 1/75 scale model of spar-type platform for 2.5 MW floating offshore wind turbine subject to one-dimensional regular harmonic wave are investigated numerically and verified by experiment. The upper part of wind turbine which is composed of three rotor blades, hub and nacelle is modeled as a lumped mass the scale model and three mooring lines are pre-tensioned by means of linear springs. The coupled fluid-rigid body interaction is numerically simulated by a coupled FEM-cable dynamics code, while the experiment is performed in a wave tank with the specially-designed vision and data acquisition system. The time responses of surge, heave and pitch motions of the scale platform and the mooring line tensions are obtained numerically and the frequency domain-converted RAOs are compared with the experiment.
https://doi.org/10.12989/sem.2015.54.5.909 인용 KSCI

Oh, Se-Young
- Communications of the Korean Mathematical Society
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- v.9 no.3
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- pp.753-765
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- 1994
The linearly constrained quadratic programming(QP) considered is : $$ min f(x) = c^T x + \frac{1}{2}x^T Hx $$ $$ (1) subject to A^T x \geq b,$$ where $c,x \in R^n, b \in R^m, H \in R^{n \times n)}$, symmetric, and $A \in R^{n \times n}$. If there are bounds on x, these are included in the matrix $A^T$. The Hessian matrix H may be positive definite or negative semi-difinite. For large problems H and the constraint matrix A are assumed to be sparse.
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Yoon, Je-Won;Kim, Young-Chan;Jang, Kang-Seok;Hong, Byung-Kook
- Proceedings of the KSR Conference
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- 2011.10a
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- pp.2844-2851
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- 2011
The purpose of this study is to set up an acoustic prediction technique and to perform the IL test of scale down noise reducing device for the development of the noise reducing device as the development of 400km/h class high speed train. First of all, the IL prediction of noise reducing device was performed with the 2D BEM method. And the noise test of scale down noise reducing device in anechoic chamber was performed for the verification of acoustic prediction technique and IL performance evaluation. As the results, the acoustic prediction technique for the development of noise reducing device was verified because the averaged IL difference between prediction and test is in 2dB(A). And the measured IL value of noise reducing device is less than 2dB(A), and additional IL with polyester absorption material is increased about 0.5dB(A).
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